Markdown links to .md documents broken after rendering

[mkende]

Describe the bug
Markdown links whose targets are .md documents work correctly in preview-mode but not after rendering.

To Reproduce
Steps to reproduce the behavior:

1. Go to any markdown page of a wiki and edit it.
2. Create a link of the form text including the final .md in the file name.
3. Observe that the link works correctly in the preview-pane (it links to the document or creates it if it does not yet exist).
4. Save and go to the rendered page. The link is rendered as a link to the current page.

Expected behavior
The link should lead to the target document.

This was working before 2.1.113. Pages which such links that are re-rendered with 2.1.113 gets broken link.

Host Info (please complete the following information):

• OS: Debian stable
• Wiki.js version: 2.1.113
• Database engine: SQLite

[mkende]

This is still happening in 2.2.51: links whose targets are written with a final .md work correctly in preview mode, but are rendered as links to the current page.

This is not very bad as one can just remove the .md extension in the link target, but it limits the compatibility with other markdown system.